Real-time energy monitors reduce costs and use (© The Energy Detective)

The TED handheld device helps homeowners track energy use in real time. // © The Energy Detective

Tom Tassi's $300 electricity bill had become an embarrassment.

"It was a joke," says Tassi, a Kenosha, Wis., resident who runs a six-person computer-service company. "The lady across the street would bring her electric bill to show me."

Her bill, for a similar house, was less than half what he was paying, Tassi says.

He replaced his windows, electric furnace and refrigerator with energy-efficient models. His local utility performed two energy audits. He added insulation.

"I can heat the inside of my house with a lighter," he says.

But his bills remained high. So Tassi became an early adopter of home-electricity monitors. He started using a new device to find where the waste was in his home and how he could reduce his bills. (Bing: Find a home-electricity monitor for your home)

Unlike smart meters, which allow homeowners to view their total usage only after a delay, home-electricity monitors tell consumers specifics about their energy use and what it's costing them in real time. The device connects to a home's breaker box, from which it wirelessly transmits the information to a smartphone-like display unit.

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Moving around the house with the handheld device, homeowners can immediately see the difference that each light or appliance makes in their total power consumption and bill. They can also view the data online using software that comes with the monitor or with free online tools such as Google's PowerMeter and Microsoft's Hohm.

This could have a profound impact on power consumption. Homeowners who can monitor their electricity usage in real time cut their power consumption an average 9.2%, according to a survey of 36 studies by the American Council for an Energy-Efficient Economy, in Washington, D.C. When homeowners have real-time feedback about individual appliances, the savings were 12%.

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Katy Bachman, a travel agent who works from her house in Cape Coral, Fla., bought a home monitor last August and downloaded a meter application, which she checks throughout the day. Seeing that her consumption rose when she turned on her electric oven to heat up an individual pizza for lunch, she bought a toaster oven and now uses it or her microwave as much as possible. She also runs her pool pump less and keeps her air conditioning a few degrees warmer.

The result: a 20% reduction in her power consumption.

Instant savings
These monitors "should be as widespread as TV sets," says Jon Wellinghoff, chairman of the Federal Energy Regulatory Commission. He purchased a monitor for his house last fall and says he cut his home power consumption and his electricity bill by 3% to 5% so far.

Installations usually require an electrician because the base unit connects to a home's circuit-breaker box and nearby wiring. But once they're running, the monitors are as easy to use as reading a meter.

Tassi, a former electrician, installed his system himself. He bought a TED 5000c, made by Energy Inc. of Charleston, S.C. The $240 device, whose initials stand for "the Energy Detective," measures how much electricity his house is using and how much it is costing him, minute by minute. It wirelessly transmits the data to a handheld device.

After installing the system, Tassi started wandering around his house with the wireless reader. He turned on the dishwasher and the television and watched his power consumption increase. He also carried around a lamp and plugged it into different outlets.

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In most outlets, the lamp used two cents' worth of power an hour. But in three outlets, the lamp was sucking up six cents. Those outlets, it turns out, had loose wires.

"It was a super nothing fix," Tassi says.

The jackpot
The real revelation was yet to come.

"I turned on the lights in the basement." Tassi says. "There were four fluorescent bulbs down there, and my electric usage went from 12 cents an hour to 86 cents an hour. I thought there was something wrong."

Tassi called Energy Inc.'s tech support, assuming he had installed his monitoring system incorrectly. After all, his energy auditors had praised him for using fluorescent bulbs that were more efficient than incandescent lighting.

But the bulbs weren't the problem. He took off the lighting fixture and noticed that the ballasts, tiny devices that limit currents in the circuits, were literally leaking electricity and had darkened the adjacent wood. For 20 years, this waste and fire hazard went undetected.

"I always assumed that the fluorescent bulbs couldn't be the problem," he says, but the faulty fixtures "were costing me $100 a month."

He replaced the fixtures and bulbs with LED lights. Now he says he can turn on a half-dozen LED lights and his hourly power consumption "doesn't even move a penny."

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On the lookout
Since September, Tassi has replaced most of his fluorescent and incandescent bulbs with LED lights, and he is more vigilant about unplugging devices that aren't in use. The handheld display stays in the kitchen, where he keeps an eye on how much power he and his wife are using.

"I know my electricity usage should be about 10 cents an hour," he says. "When it gets up to 13 cents, I know there's something on somewhere that shouldn't be."

He says he usually walks through his house looking for a lamp or computer that has been left on.

His most recent electricity bill was $85. He's now thinking of lending the system to friends and neighbors.

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Tassi makes a point of showing off his latest bills to his neighbor across the street. Some months, he spends less than she does. But the real satisfaction is in knowing that he is no longer wasting his money.

"One day it hit me," Tassi says. "Holy mackerel, I've been throwing money away for years."

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